Magnetic head having two main magnetic poles, magnetic disk apparatus and magnetic head switching control circuit

Abstract

A magnetic head structure is disclosed which can avoid the problem of side erasing regardless of whether the skew angle is assigned to the positive side or negative side while ensuring write magnetic field intensity. The magnetic head includes at least two main magnetic poles having a single taper shape as a plane shape of a tip thereof opposite to a recording medium and axially symmetrically disposed with respect to a longitudinal direction of a slider, a return yoke for returning a write magnetic field generated by the main magnetic poles, and thin-film coils assigned to each of the main magnetic poles.

1 . A magnetic head; comprising:
 at least two main magnetic poles having a single taper shape as a plane shape of a tip thereof opposite to a recording medium and axially symmetrically disposed with respect to a longitudinal direction of a slider;   a return yoke for returning a write magnetic field generated by the main magnetic poles; and   thin-film coils assigned to each of the main magnetic poles.   
     
     
         2 . The magnetic head according to  claim 1 , wherein the single taper shape in a plane of the tip of the main magnetic pole is a shape in which the main magnetic pole becomes wider from a leading edge side to a trailing edge side, which is a traveling direction of the magnetic head relative to the recording medium. 
     
     
         3 . The magnetic head according to  claim 1 , wherein when at least two main magnetic poles are disposed, a magnetic shield made of soft magnetic material is formed between the adjacent main magnetic poles. 
     
     
         4 . The magnetic head according to  claim 1 , comprising a trailing shield type write magnetic element disposed at the tip of the return yoke with a soft magnetic material on a side closer to the tip of the main magnetic pole. 
     
     
         5 . The magnetic head according to  claim 1 , comprising a cusp coil type write magnetic element, wherein a coil is formed by sandwiching the main magnetic pole from above and from below with the thin-film coils having at least two layers. 
     
     
         6 . A magnetic disk apparatus; comprising:
 a magnetic head having at least two main magnetic poles having a single taper shape as a plane shape of a tip thereof opposite to a recording medium and axially symmetrically disposed with respect to a longitudinal direction of a slider, a return yoke for returning a write magnetic field generated by the main magnetic poles, and thin-film coils assigned to each of the main magnetic poles; and   a recording medium.   
     
     
         7 . The magnetic disk apparatus according to  claim 6 , wherein the single taper shape in a plane of the tip of the main magnetic pole is a shape in which the main magnetic pole becomes wider from a leading edge side to a trailing edge side, which is a traveling direction of the magnetic head relative to the recording medium. 
     
     
         8 . The magnetic disk apparatus according to  claim 7 , wherein a point where a skew angle of the magnetic head becomes 0° on the recording medium is defined as a reference point, and recording is performed on an inner circumferential side from the reference point by a first main magnetic pole disposed in such a way that the plane of the tip of the main magnetic pole has a taper shape toward an inner circumferential direction of the recording medium and recording is performed on an outer circumferential side from the reference point by a second main magnetic pole disposed in such a way that the plane of the tip of the main magnetic pole has a taper shape toward an outer circumferential direction of the recording medium. 
     
     
         9 . The magnetic disk apparatus according to  claim 6 , wherein recording by first and second main magnetic poles is switched by a write current control part and a write data buffer part of a head amplifier in accordance with polarity of a skew angle. 
     
     
         10 . A magnetic head switching control circuit, wherein a main magnetic pole to be used is selected from and recording is instructed to two or more main magnetic poles of a magnetic head disposed in accordance with cylinder address of a recording medium and head address of the magnetic head. 
     
     
         11 . The magnetic disk apparatus according to  claim 6 , comprising the magnetic head switching control circuit.